The act of pissing in a girl's mouth when you actually think you are ejaculating. with it--and he simply pulls his penis out and begins peeing all over her head. Learn about the causes of painful urination or dysuria from the Cleveland Clinic, including symptoms like burning and causes like urinary tract infection. 20 Apr I am a 17 year old male and I was wondering why I sometimes involuntarily urinate when the head of my penis is stimulated. I am thinking of.